Top 10 Most Harmful Decisions from U.S. Presidents

This list denotes the most harmful decisions. Not the worst decisions politically or in terms of career, so sex scandals and such are sort of off the table.
The Top Ten
1 Declaring a second war on Iraq (George W. Bush)

9/11 just wasn't an excuse to justify declaring war on Iraq because they also killed and wounded many innocent civilians. You really can't have all civilians survive a war, can you?

A war against WMD's that never existed. Not only did the war cost 2 trillion dollars and lots of lives, but it destabilized the entire middle east into chaos.

2 Vietnam War (Lyndon Johnson)

America had no reason to get directly involved in the Vietnam War. They instead could've just sent supplies to South Vietnam, but no, they just had to get involved in it, which led to thousands of deaths there. Many people also died back in America, like in Kent State in 1970, where 4 people were killed by the national guard after protesting the invasion of Cambodia.

It was an unnecessary war, as the domino theory proved false. The draft was reinstituted. A lot of money and lives were lost. And it ruined public trust in the government for generations.

3 Allowing the South to secede (James Buchanan)

The Civil War was prone to happen anyway, but on top of an entire term of placating southern slaveowners, his decision to do absolutely nothing as Southern states left the union was appalling. The war may have been unpreventable, but he could have at least tried to have done something.

Buchanan was simply honoring his oath to the Constitution (imagine that). Secession was lawful; no permanent Union was created by ratification of the Constitution. So what's your point?

4 Japanese American Interment (Franklin Delano Roosevelt)

The rounding up of thousands of Japanese Americans, taking them away from their jobs/families/businesses and putting them into camps was racist and oppressive.

5 Fighting a second war with Britain (James Madison)

It was an avoidable war for American pride, and for stealing Canadian land from the Indians. The White House was attacked and the existence of the United States itself was in danger.

6 Abolishment of the Nuclear Arms Treaty (Donald Trump)

Trump had to do it, Obama's deal was the worst thing ever, and virtually guaranteed a major showdown in 10-15 years time.

7 The Phillipines-American War (Theodore Roosevelt & William McKinley)

Despite being only briefly mentioned in history books, this early 1900's genocide was a case of the United States using cruel and violent tactics to colonize the Phillipines.

8 The War on Drugs (Richard Nixon)

Nixon's own advisors later admitted it was a tool just to suppress hippies and blacks, but nonetheless, The Controlled Substances Act resulted in the incarceration of millions of people for small marijuana possession as well as punishing severe addicts instead of helping them.

9 Building a wall (Donald Trump)
10 The Embargo Act (Thomas Jefferson)

Wanting to stay neutral in foreign affairs, Jefferson banned American trade with both Britain and France. It resulted in a short-term depression and it hurt a lot of poor/working people.

The Contenders
11 Bay of Pigs Invasion (John F. Kennedy & Dwight Eisenhower)

The decision to stage a failed coup in Cuba, on the false assumption that most of its citizens would support it resulted in the Cuban Missile Crisis, which had nuclear missiles positioned that could destroy the entire country. Thankfully, he handled it successfully.

This just almost caused a nuclear war.

12 Withdraw from the Paris agreement (Donald Trump)
13 Hawley-Smoot Tariff (Herbert Hoover)

Despite the explicit warning by many economists, Hoover's belief in protectionism drove him to sign it anyway. This resulted in a trade war which made the Great Depression even worse.

14 Alien and Sedition Acts (John Adams)

They suppressed freedom of speech which was the first amendment and made it much harder for immigrants to get jobs. The Virginia and Kentucky Resolutions were passed because of these acts. The resolutions were also one of the causes for Civil War.

15 Indian Removal Act (Andrew Jackson)
16 The Federal Reserve Act (Woodrow Wilson)
17 New Deal (Franklin Roosevelt)

This prolonged the great depression by at least 7 years.

18 Afghanistan withdrawal (Joe Biden)
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